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      <p>The C API for the Berkeley DB Logging subsystem was reworked in the 4.0
release as follows:</p>
      <div class="informaltable">
        <table border="1" width="80%">
          <colgroup>
            <col />
            <col />
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          <thead>
            <tr>
              <th>Historic functional interface</th>
              <th>Berkeley DB 4.X method</th>
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            <tr>
              <td>log_archive</td>
              <td>
                <a href="../api_reference/C/logarchive.html" class="olink">DB_ENV-&gt;log_archive()</a>
              </td>
            </tr>
            <tr>
              <td>log_file</td>
              <td>
                <a href="../api_reference/C/logfile.html" class="olink">DB_ENV-&gt;log_file()</a>
              </td>
            </tr>
            <tr>
              <td>log_flush</td>
              <td>
                <a href="../api_reference/C/logflush.html" class="olink">DB_ENV-&gt;log_flush()</a>
              </td>
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              <td>log_get</td>
              <td>
                <a href="../api_reference/C/logcursor.html" class="olink">DB_ENV-&gt;log_cursor()</a>
              </td>
            </tr>
            <tr>
              <td>log_put</td>
              <td>
                <a href="../api_reference/C/logput.html" class="olink">DB_ENV-&gt;log_put()</a>
              </td>
            </tr>
            <tr>
              <td>log_register</td>
              <td>DB_ENV-&gt;log_register</td>
            </tr>
            <tr>
              <td>log_stat</td>
              <td>
                <a href="../api_reference/C/logstat.html" class="olink">DB_ENV-&gt;log_stat()</a>
              </td>
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            <tr>
              <td>log_unregister</td>
              <td>DB_ENV-&gt;log_unregister</td>
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      <p>Applications calling any of these functions should update their calls
to use the enclosing <a href="../api_reference/C/env.html" class="olink">DB_ENV class</a> handle's method (in all cases other
than the log_get call, this is easily done as the first argument to the
existing call is the correct handle to use).</p>
      <p>Application calls to the historic log_get function must be replaced
with the creation of a log file cursor (a <a href="../api_reference/C/logc.html" class="olink">DB_LOGC class</a> object), using
the <a href="../api_reference/C/logcursor.html" class="olink">DB_ENV-&gt;log_cursor()</a> method to retrieve log
records and calls to the <a href="../api_reference/C/logcclose.html" class="olink">DB_LOGC-&gt;close()</a> method to destroy the cursor.  It
may also be possible to simplify some applications.  In previous
releases of Berkeley DB, the DB_CURRENT, DB_NEXT, and DB_PREV flags to the
log_get function could not be used by a free-threaded <a href="../api_reference/C/env.html" class="olink">DB_ENV class</a>
handle.  If their <a href="../api_reference/C/env.html" class="olink">DB_ENV class</a> handle was free-threaded, applications
had to create an additional, unique environment handle by separately
calling <a href="../api_reference/C/envopen.html" class="olink">DB_ENV-&gt;open()</a>.  This
is no longer an issue in the log cursor interface, and applications may
be able to remove the now unnecessary creation of the additional
<a href="../api_reference/C/env.html" class="olink">DB_ENV class</a> object.</p>
      <p>Finally, the <a href="../api_reference/C/logstat.html" class="olink">DB_ENV-&gt;log_stat()</a> call has been changed in the 4.0 release
to take a flags argument.  To leave their historic behavior unchanged,
applications should add a final argument of 0 to any calls made to
<a href="../api_reference/C/logstat.html" class="olink">DB_ENV-&gt;log_stat()</a>.</p>
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